The high level of failure of endocardial defibrillation leads has pushed the medical device industry to offer a subcutaneous alternative know as Subcutaneous ICD (S-ICD) whose basic idea is to remove the defibrillation leads from the circulatory system and the heart cavities.
However, S-ICD is not free from risk or difficulty. Apart from the surgical risks, clinical studies involving S-ICD have raised new issues and have shown that S-ICD has not reduced the occurrence of known problems associated with standard implantable defibrillators. The technique has nevertheless been accepted by the medical community because it excludes leads from the venous circulatory system, especially the heart chambers. Exclusion from the heart chambers is very appealing to the medical community as the heart is a sensitive area for patient safety and typically the most severe environment for the leads inducing specific risks related to the mechanical stresses applied to the device.
One of the major drawbacks of S-ICD is the energy level required by the new configuration, which is about twice that of the standard implantable defibrillator. Further, implementation of S-ICD requires the design of a new case, leads, electrodes, installation accessories, and training for the practitioner.